Rack storage apparatus

ABSTRACT

There is described a multi-shelf storage rack having spaced shelf-supporting uprights arranged in pairs, each pair comprising a front and a rear upright, the uprights having two rows of vertical notches extending vertically thereof in which the shelves are supported. At least some of the shelves have a pair of transverse rails extending from the front to back with a stop at the back. A wheeled dolly is positioned on these rails and the dolly has a spring-biased latch pin that restrains it against movement on the rails. An outrigger, comprising a structural frame, can be hung on the uprights in position in front of a selected shelf, secured against accidental removal whereupon a latch pin-releasing device on the outrigger may be operated to release the latch pin on the dolly and the forward end of the dolly rolled from the rails on the shelf onto matching rails on the outrigger to a position where the dolly is exposed vertically for loading or unloading by a crane or hoist. When loading or unloading is completed, the dolly is rolled back onto the shelf and an inclined ramp on the outrigger retracts the latch pin on the dolly until the dolly is back on the shelf when the latch pin will spring into latching position. The outrigger is thereafter lifted off the rack by the crane or hoist and placed on the floor or hung in front of another shelf.

United States Patent [191 Saul, Jr. et al.

[ RACK STORAGE APPARATUS [75] Inventors: Samuel Saul, J r. Pittsburgh;Thomas D. Colbridge, Chalkhill, both of Pa.

[73] Assignee: Rack Engineering Company,

Connellsville, Pa.

[22] Filed: Oct. 8, 1971 [21] Appl. No.: 187,608

Primary Examiner-Gerald M. Forlenza Assistant Examiner-R. B. JohnsonAttorney-William H. Parmelee [57] ABSTRACT There is described amulti-shelf storage rack having July 3,1973

spaced shelf-supporting uprights arranged in pairs, each pair comprisinga front and a rear upright, the uprights having two rows of verticalnotches extending vertically thereof in which the shelves are supported.At least some of the shelves have a pair of transverse rails extendingfrom the front to back with a stop at the back. A wheeled dolly ispositioned on these rails and the dolly has a spring-biased latch pinthat restrains it against movement on the rails. An outrigger,comprising a structural frame, can be hung on the uprights in positionin front of a selected shelf, secured against accidental removalwhereupon a latch pin-releasing device on the outrigger may be operatedto release the latch pin on the dolly and the forward end of the dollyrolled from the rails on the shelf onto matching rails on the outriggerto a position where the dolly is exposed vertically for loading orunloading by a crane or hoist. When loading or unloading is completed,the dolly is rolled back onto the shelf and an inclined ramp on theoutrigger retracts the latch pin on the dolly until the dolly is back onthe shelf when the latch pin will spring into latching position. Theoutrigger is thereafter lifted off the rack by the crane or hoist andplaced on the floor or hung in front of another shelf.

8 Claims, 12 Drawing Figures PAIENTEuJuL 3 I973 3143.1 15

SHEEI 1 0F 4 V w INVENTOR-i SAMUEL SAUL, .1. and mamas o. co; BR/DGEtheir A Home]:

PATENTEDJUL 3191s 3.143.115

. 20 2/ INVENTORS SAMUEL SAUL, Jr. and (a THOMAS 0. COLBR/DGE I el'rAlfomeys PATENIEnJuL 3 I975 SHEEI 3 [If 4 w v I i I I g I I l Illa m wETII'IIUHIIII'III I F II IH II II IHI I I IH 5 l8 3 H w 4 a m C w a l 31 E h'mm r m w n m SAMUEL SAUL, Jr. and THOMAS 0. COL BRIDGE MeirAllorncys PAIENIEnJuL 3191s saw u or 4 INVENTO/PS moms a. 601. 50/005LIII V Mair Attorneys RACK STORAGE APPARATUS This invention relates tomaterial storage equipment for use particularly in industries and otherplaces where heavy loads are placed on and removed from multishelvedracks by the use of an overhead traveling hoist or crane.

In many manufacturing industries, as well as elsewhere, storage racksare provided which are typically but not necessarily from twelve totwenty feet in height, with notched front and rear uprights at regularintervals that support adjustable shelves. Commonly there may be two ormore rows of such racks in parallel relation with an aisle between eachtwo confronting racks. The shelves to which this invention relates areused for the most part to store heavy articles, such for example asspare or replacement parts for machinery used in a manufacturingoperation, heavy die blocks, or even inventory of parts used in theassembly of products or completed inventory of manufactured articles. Inother instances, such storage racks may be used in warehouses andstorerooms of various kinds. In any event, the articles placed on theshelves are frequently of a nature that require, or at least makeadvantageous, the use of an overhead traveling crane or hoist forbringing articles to or carrying them from the storage racks asdistinguished from placing the load on a pallet and putting it intoplace or removing it from the shelf with a fork lift truck. However, thecranes can only effectively lift or lower a load vertically, but cannot,in most cases maneuver a heavy article into a selected shelf or removeit from the shelf where there are one or more shelves above it,especially if the shelves, as is usually the case, are at most only twoor three feet apart. Considerable manual labor and time, therefore, maybe required for the placing of an article or load on a shelf or removingit therefrom. Moreover, it is an operation not free of danger to aworkman who may be on a ladder trying to swing the load into place.

It has heretofore been proposed to provide trackforming rails on eachshelf, with each shelf having a wheeled dolly movable on said rails.Removable bridge bars are put in place extending from a shelf on oneside of the aisle to a shelf on the other side, and the dolly may berolled from the tracks on the shelf onto matching rails on the bridgebars whereupon the overhead hoist may lower a load onto the dolly orlift therefrom after which the dolly is rolled back into position on theshelf. Often loads of as much as a ton or more are handled in this way,but this procedure has several drawbacks. One drawback is that thepositioning of the columns and the level of the shelves on each side ofthe aisle must be matched so that the bridge bars will be level, andanother drawback is that there may be a row or rows of shelving wherethere is no confronting row of shelves on which such bridge bars can berested. In addition, there is a safety hazard because if a dolly is notproperly restrained on the shelf or is prematurely released the dollymay roll off the shelf resulting in considerable damage and possibleinjury to a worker.

The present invention is designed to overcome these dangers andshortcomings and provide a space-saving storage system where heavy loadscan be placed on or removed from the storage rack shelves with greaterfacility and safety and without regard as to whether one row of shelvingconfronts another or whether the shelves and columns at one side of theaisle are directly across from each other or are at the same level.

According to our invention there is provided an outrigger that may bewheeled along the shop floor to a selected position, then lifted withthe crane or hoist to the level of the shelf to be loaded or unloadedand hooked into the notched uprights at each end of the selected shelf.In this operation a workman will generally ride up on the outrigger andimmovably secure it in position on the columns. Once the outrigger issecured on the rack the crane or hoist is disconnected. The outriggerhas rails on the top thereof that will align with rails on the shelf.The dolly has an interlocking latching engagement with the shelf thatcan be released only when the outrigger is in place, so that the dollycannot roll forward until at least a considerable portion of it ispositioned over and supported by the outrigger after this safetyinterlock has been released. The latching means snaps back intorestraining position when the dolly is rolled from the outrigger backonto the shelf.

The outrigger is preferably provided with means to limit the travel ofthe dolly to a position where the major portion of the area of the dollyis clear for the placing of a load thereon or removing a load therefrombut the wheels at the inner end of the dolly-will not move off theshelf. Thus, part of the weight of the load is always supportedvertically in the rack structure and part of it is transmitted to thecolumns as lateral components of thrust and tension to preventoverstressing of the rack structure.

During the actual transfer of the load to or from the hoist to the dollythe workman will be on a safety ladder adjacent the outrigger at alocation where he can secure or release the books or sling connectingthe load and the hoist.

The invention may be fully understood by reference to the accompanyingdrawings showing a preferred embodiment of our invention and in which:

FIG. 1 is an end view of a storage rack showing the outrigger in fulllines on the floor at the base of the rack, while the drawing also showsthe outrigger in phantom lines at an elevated position on the rack.

FIG. 2 is a front elevation of a portion of rack with several shelvesand with a dolly on each of two of the shelves.

FIG. 3 is a horizontal section in about the plane of line III-III ofFIG. 2 but on a larger scale.

FIG. 4 is a fragmentary front view of FIG. 3.

FIG. 5 is a transverse fragmentary vertical section in the plane lineV-V of FIG. 3.

FIG. 6 is a plan view of the dolly but with portions thereof broken awayto better disclose the structure.

FIG. 7 is a front view of the dolly shown in FIG. 6.

FIG. 8 is a plan view of the outrigger showing it attached to the frontcolumns of the rack, these columns being shown in section and the rackshelf and the dolly are omitted for better illustration.

FIG. 9 is an end elevation of FIG. 8.

FIG. 10 is a fragmentary vertical section on a larger scale showing aportion of the outrigger attached to the front column of the rack withportions of the shelf and dolly.

FIG. 11 is a fragmentary side elevation on a larger scale and partly insection of the safety locking pin on the dolly.

FIG. 12 is a front elevation of the outrigger with the removable liftingbar, by which the outrigger is hoisted into place.

Referring to the drawings, the rack structure itself may take severaldifferent forms, the one here shown being generally similar to thatshown in US. Pat. No. 2,729,342 granted Jan. 3, 1956 to Samuel Saul, Jr.one of the present inventors.

The rack has spaced vertical front supporting posts 2 and spaceddirectly behind them are rear posts 3. Each post has two vertical rowsof notches 4 therein providing hook-like projections 4a between each twonotches. There are two rows of notches so that each pair of one frontand one rear upright will support one end of each of two shelves, as iswell understood in the art.

The shelves are designated generally as 5 and in a given installation itis desirable that any shelf be interchangeable with any other shelf. Theshelves each have a structured section 6 across the front, preferably achannel section with the web vertical and the flanges turned toward thefront of the rack. There is a similar section 7 at the back of theshelf. There are transverse sections 8 extending from front to rear neareach end of the shelf and intermediate sections 9 also extending fromfront to rear. At each corner of the shelf there is a mounting structure10 adapted to be fitted and hooked into the notches and hooks of theuprights to hold the shelves in place and restrain them against lateralor fore and aft movement. Each mounting structure 10 is constructed toengage in two notches on the upright with which it is hung. Each shelfmay therefore be set in the upright at any selected elevation, all asdescribed in said U.S. Pat. No. 2,729,342.

Each shelf with which the present invention is particularly concernedalso has a pair of rails 11 preferably in the form of inverted anglesections positioned over the sections 8 near each end of the shelf. Eachrail 8 has its front end extending across the top of the front channelsection 6 (see FIG. 3) but at its rear end there is a stop member 12 toprevent the hereinafter described dolly from rolling off the shelf atthe back, so that the rail 11 stops forwardly of the rear structuralshelf section 7. The stop 12 is positioned above said section at the endof each rail. Since all shelves are interchangeable the rails on allshelves which are provided with rails are the same and are spaced thesame distance apart. It may be, however, that in some installations someof the shelves may not be equipped with rails 11 where it may be moreconvenient to merely place a loaded pallet on some particular shelf orshelves, especially the lower ones that can be loaded or unloaded with afork lift truck. The present invention is used where at least some ifnot all of the shelves have rails and stops, as here provided.

Each shelf that is equipped with the rails 11 is designed to receive adolly, designated generally as 15 which has four grooved wheels 16 onthe underside thereof, one near each corner and with the front and backwheels at each side of the dolly in alignment, so that one pair of frontand back wheels will ride on one rail 11 and the other pair on the otherrail and the V- shaped groove inthe peripheries of the wheels will guidethe dolly on the inverted V-shaped rails 11. Each dolly, as best seen inFIG. 6 has a frame of structural sections 17 and 18, the sections 17being at the front and rear of the dolly and 18 designates the othersections. There is a deck plate 19 over the bed of the trolly and it isdesirably surrounded by front, rear, and side wall structures 20 forassuring that articles or loads placed on the dolly cannot slide off thedeck of the trolley.

At the center of the front cross member 17 of the dolly there is weldeda latch pin assembly designated generally as 21 as shown in FIG. 1 1. Itcomprises a vertical barrel 22 having a slidable latch pin 23 projectingfrom its lower end. The pin has an upwardly extending stem 24 thatpasses through an abutment or disk 25 fixed in the upper end of thebarrel. There is a compression spring 26 in the barrel around the stemconfined between the top of the pin 23 and the disk 25 to resilientlyurge the pin to a fully projected position while a stop 27 on the inneror upper end of the stem 24 limits the outward movement of the pin,which, however, may be pressed inwardly against the pressure of thespring. The spring is desirably a strong spring, so strong in fact thata workman cannot press the pin in with his hands, or at least notwithout great effort. There is an end piece 28 at the top of the barrelwelded to the barrel so that one cannot tamper with the latch pin orspring from the upper end of the assembly.

The latch pin is so positioned on the cross member 17 that when thedolly is pushed onto the shelf against the stops 12 at the rear ends ofthe rails l 1 the latch pin will project down below the top of the frontshelf rail 6 and thereby prevent the accidental removal of the dollyfrom the shelf. It is only possible to remove the dolly by raising thelatch pin high enough to clear the top of the shelf section 6 and this,for all practical purposes cannot be done by one trying to push the pinup with his hand.

The third element of the combination is the outrigger itself. It isdesignated generally as 30 and has a structural frame of a widthsubstantially equal to the width of the shelf in an end-to-enddirection, that is, at least equal to the distance required to reachfrom a row of hooks and notches on one column to a row of hooks andnotches on an adjacent column. There is a rectangular base frame ofstructural sections including front and rear sections 31 and for and aftsections 32 at the ends and intermediate the ends. There are casters 33at each corner of the base at least two of which swivel, as indicated inthe drawing. The central area of the front of the base has a platform 34thereon which is desirably formed of expanded metal (see FIG. 8) onwhich a workman may stand.

At each comer of the base there is a corner post 35 which supports anupper frame structure comprising an elongated rear section 36, endsections 37, front sections 38, each of which extends from a frontcorner post 35 to an upright 39 leaving an entrance at 40 through whicha workman may step onto the platform 34. There are desirably tubularposts 41 at each side of this entrance onto which a workman may hold anda safety chain 42 may be hooked across the entrance, as indicated inFIGS. 1 and 12. There is another vertical and diagonal bracing, asindicated, between the upper and lower frames and the structure iswelded to give it complete rigidity. Spaced inwardly from each end ofthe upper frame are horizontal struts 43 that extend from thebacksection 36 to one of the front sections 38 and there are rails 44,similar to the rails 11 on the shelves, mounted on each of these struts.These rails extend from the rear edge of the upper elongated section 36to a stop element 45, similar to the elements 12, and they are locatedat the front ends of the rails 44. The spacing and location of the rails44 on the outrigger is such that when the outrigger is hung on the frontof the rack for cooperation with a selected shelf, as hereinafterdescribed, the rails 44 of the outrigger will be in exact alignment withthe rails 11 on the selected shelf and, in effect, then provide acontinuation of the rails 11.

There is welded to each rear corner ofthe outrigger a mounting piece 50for hanging the outrigger on two front columns of the rack structure.This mounting piece as here shown is a structural T-section with the legof the T projecting to the rear. Near its upper end it has a short bar51 of a slightly angled section passing therethrough and rigidly weldedthereto. Near the lower end of the leg of the T-section there is asecond similar cross bar 52. The vertical spacing between these two barsor cleats 51 and 52 from the lower edge of one to the lower edge of theother exactly corresponds to the distance from the bottom of one notch 4in the upright 2 to the bottom of the fourth notch below it, as shown inFIG. 9, that is, the edge-to-edge distance is a multiple of thecenter-to-center distance between notches on the uprights, so that whenthe outrigger is brought to a proper level to align the rails 44 withthe rails 11 on the shelf the cross bars or cleats 52 will engage thebottoms of two spaced notches in the uprights. Moreover, as seen in FIG.8 the cleats project from each side of the leg of the T-section farenough to engage in the corresponding notches of both vertical rows ofnotches on the same column so that the load or stress on each cleat isexerted against two hooks on the column.

At each top rear corner of the outrigger there is a yoke comprised oftwo rigid arms 55 the free terminal portions of which curve slightlyaway from each other. Each yoke straddles one of the upright columns(See FIGS. 8 and 9) as the outrigger is moved by a hoist into positionto be hung on the columns and aids in guiding the cleats 51 and 52 intothe notches of the upright columns and exactly aligning the rails on theoutrigger with those on the shelf.

There are aligned holes 56 in the terminal portions of the two arms 55.There is a removable safety device best seen in FIG. 8 in the form ofan'angled connecting bar with a long pin 57 at one end thereof and ashort pin 57a at the other end, the two pins being parallel. When theoutrigger is in place, a workmanstanding on the platform of theoutrigger holding the connecting bar inserts the long pin of the safetypin device through the aligned holes 56 in the two arms of the yoke atone end of the outrigger while the short arm passes through the formednotch portion 4 in the upright just under one of the hooks 4a. Theoperation is repeated with a second safety device at the other corner.The long pin of the safety device forms a tie between the two arms ofthe yoke at the back of the upright of the rack so that the outriggercannot pull away from the upright so long as the safety device is inplace and the short pin 570 being rigidly connected to the first willenter the notch below the yoke and wedge against the under surface ofthe hook 4 beneath which it is located and prevent the yoke andoutrigger from being .accidentally raised or lifted to a level where thecleats 51 and 52 could move up in the notches in which they are engaged,or even to a level that would lift the track rails of the outriggerabove the level of the track rails on the shelf. 'Ihere is usual type ofspring ball detent in the free end of the longer pin member 57 at 58 toprevent accidental displacement of this safety element.

For lifting the outrigger from the floor to the shelf level at which itis to be used there is a lifting extension 60 secured to and extendingupwardly from each of the upper end sections 37 of the outrigger. Belowits upper end each extension has an inverted hook-like notch 61 thereinand above the notch the extension has a hole 62 therethrough. Theextensions 60 are positioned at about the center of the end pieces 37 towhich they are secured so that when the outrigger is being lifted ashereinafter described, it will stay nearly level but can be easilytilted to a slight extent by the workman on the platform shifting hisweight.

There is a removable lifting bar 65 of rectangular section with reducedrectangular end portions 66 at each end. This bar is slightly longerthan the distance from one lifting extension 60 to the other and the endportions of this bar can be slipped sideways under and up into the bightof the hook-like notches 61. Near each end of the top edge of the barthere is a toggle lever operated latching pin unit 67 of a well knowntype so positioned' that when the lifting bar is in place the latchingpin can be projected into the adjacent hole 62 of the lifting extension(See FIG. 12) and thus retain the lifting bar in position until thelatching pins are retracted. At the center of the lifting bar there is alifting ball 68 into which the lifting hook of a crane or hoist can beengaged.

After the outrigger has been secured in place in front of a selectedshelf and the lifting bar 65 has been released and carried away by thehoist, it is necessary to release the latch pin 21 from its lockingposition against the rear section 6 at the front of the shelf before thedolly can be moved forward onto the rails of the outrigger. For thispurpose there is a shaft 70 mounted in bearings 71 below the level ofthe rails 44 and the rear top cross bar 36 of the outrigger (See FIG.9). This shaft is slidable endwise in the bearings and also is rotatableand has a crank 72 at its forward end above the platform 34. The rearend of the shaft has a somewhat quadrant shaped eccentric cam 73 on itsrear end. There is a hub 74 fixed on this shaft with two diametricallyopposite spokes or arms 74. radiating therefrom, each of which is longenough to contact the depending leg of a downwardly and forwardlysloping T-section 75 (See FIG. 10) that has its top surface at one endflush with the top of the rear section 36 of the outrigger and itsforward end resting on long frame member or bracing section 76 extendingbetween the two struts 43 but the top of which is lower than the top ofthe rear rail 36. These spokes limit the arc through which the shaft 70may rotate in either direction to 180 or slightly less because one willcontact one side of the leg of the T- section 75 when the shaft rotatesone direction and the other arm will strike the other side when theshaft is rotated in the opposite direction.

Finally, there is a spring 77 attached to one arm 74 and anchored to theframe member 76 and this spring resiliently restrains the shaft fromsliding rearwardly and also biases the shaft to return to a positionwhere the cam 73 is in the position shown in FIG. 8.

To release the latch pin 23 of the latch 21 so that the dolly may rollfrom the shelf onto the outrigger, the workman must push the cranktoward the rear and then rotate it about until the leading end of thecam contacts the end of the latch pin. Then the continued rotation ofthe cam will lift the latch pin against the pressure of spring 26 to alevel where it just clears the shelf bar 6 and the dolly can then bepulled forward. As the pin 23 rides off the cam it slides across the topof the shelf section 6, then the top of the outrigger section 36 andthen down the sloping top of the T-section 75 until it is again fullyextended.

The stops 45 at the ends of the rails 44 are so positioned that the reartwo wheels of the dolly will never roll off the rails 11 on the shelf,as shown in the phantom outline in FIG. 1, so that the outrigger is notrequired to support the full weight of the dolly and its load. Thiseliminates excessive overhang of the load at the front of the rack, butgives'the dolly adequate exposure from above for loading or unloading itfrom a hoist.

After loading or unloading the dolly it is pushed back onto the shelf,and as it is pushed back, the top of the sloping T-section 75 willprovide a ramp that will cam the latch pin 23 back up to a level whereit will slide across the tops of the bars 36 and 6 and when the dolly isfully back the latch pin will snap down to its latching position.

From the foregoing it will be seen that the invention provides anoutrigger construction that may be wheeled from one position to anotherover the floor or carried by a crane and then hoisted to a selectedshelf with a workman riding up on the outrigger. The rack, the rackshelves, the dolly on the shelves and the outrigger all are designed foruse together, and when the outrigger has been hung on the rack at thefront of the selected shelf, the workman applies the safety devices tothe yokes to immovably secure the outrigger against displacement. Healso releases the hoisting bar 65 from the lifting extensions and thehoist takes it away. Operating the crank 72, the latch pin 23 on thedolly is released and the dolly is rolled out onto the outrigger untilits forward travel is stopped by the stops 45. As a matter of safety,the workman will have moved to a safety ladder which has been broughtinto position. The crane or hoist will lift a load from or deposit aload onto the dolly and the dolly will be pushed back onto the shelf. Asit moves back, the sloped ramp 75 will raise the latch pin 23 and itwill snap into latching position when the dolly wheels contact the backstops 12. The workman may then get back onto the outrigger, remove thedual pin safety devices, attach the hoisting bar and the crane or hoistwill remove the outrigger to return it to the floor or to another shelf.

We claim:

1. A rack type storage apparatus comprising, in combination:

a. a storage rack having a series of spaced pairs of front and rearvertically notched uprights and a series of vertically spaced shelvesextending between and supported on each two pairs of adjacent uprights;

b. at least some of the shelves having spaced rails thereon extendingfrom the front to the rear,

0. a dolly having front and rear wheels engaging said rails adapted totravel on said rails, and

d. an outrigger comprising a structural frame arranged to be elevated bya hoist to a position in front of a selected shelf on said rack, theoutrigger having hook means thereon arranged to engage the notchedupright at each end of the selected shelf for releasably supporting theoutrigger on said uprights,

e. the outrigger having rails thereon that align vertically andhorizontally with the rails on the selected shelf when the outrigger isso supported on the uprights to provide in effect an'extension of therails on the shelf whereby the dolly may roll from the shelf onto theoutrigger,

f. means on the dolly to restrain it from rolling off the shelf railswhen the outrigger is not in front of the shelf and which may bereleased when the outrigger is supported at the front of the shelf, and

g. means on the outrigger for limiting the travel of the dolly when ittravels forward onto the rails of the outrigger.

2. A rack type storage apparatus as defined in claim 1 in which saidlast named means is so positioned that the rear wheels of the dollycannot leave the rails on the shelf.

3. A rack type storage apparatus as defined in claim 1 wherein the meansto restrain the outrigger from rolling on the shelf rails when theoutrigger is not positioned on the rack in front of the selected shelfcomprises a latch on the dolly that interlocks with the shelf structureand wherein there is means on the outrigger selectively operable torelease said latch means only when the outrigger has been secured to'the uprights at the front'of the selected shelf with the rails of theoutrigger aligned with the rails of the shelf.

4. A rack type storage apparatus as defined in claim 3 wherein the latchcomprises a spring biased pin slidable within an enclosing barrel whichis secured to the dolly and having an end projecting from the barrel,the force of the spring holding the pin projected into a latchingposition, the shelf having a structural section against a surface ofwhich the pin projects when the dolly is confined against travel alongthe shelf rails, said means on the outrigger for. releasing said latchcomprising a cam on the outrigger positioned to selectively bear againstsaid pin to move it to a retracted position out of latching engagementwith said structural section of the shelf only when the outrigger hasbeen mounted on the rack with its rails aligned with the rails on therack, and means on the outrigger for operating the cam.

5. A rack type storage apparatus as defined in claim 4 wherein theoutrigger has an inclined ramp thereon in the path of travel of said pinpositioned to effect retraction of the pin into the barrel when thedolly is moved from a position off the outrigger back onto the shelf.

6. A rack type storage apparatus as defined in claim 5 wherein eachupright has a series of parallel alternate notch and hook elementsextending up each side at the front thereof and the shelves haveinterfitting mounting means at each corner engaged with the notches andhooks of the uprights, and the hook means on the outrigger comprisesvertically spaced cleats at each end of the outrigger so loc'ate'd thatnotches in the front uprights above and below the selected shelf aresimultaneously engaged for supporting the outrigger on the verticalcolumns at a level where the rails of the outrigger are aligned with therails of the selected shelf.

7. A rack type storage apparatus as defined in claim 6 wherein there arereleasable safety means on the outrigger which are confined in theiroperating position against the rear walls of the two vertical columns onwhich the outrigger is hung for preventing accidental release of theoutrigger until said safety means are withdrawn from said operatingposition to release the outrigger for removal from the uprights.

of the column when the safety means is in operating position to restrainthe outrigger against accidental upward movement of the column until thesaid safety 8. The invention as defined in claim 7 wherein said 5 meansis withdrawn from the Operating Positionsafety means has a portion thatprojects beneath a hook

1. A rack type storage apparatus comprising, in combination: a. astorage rack having a series of spaced pairs of front and rearvertically notched uprights and a series of vertically spaced shelvesextending between and supported on each two pairs of adjacent uprights;b. at least some of the shelves having spaced rails thereon extendingfrom the front to the rear, c. a dolly having front and rear wheelsengaging said rails adapted to travel on said rails, and d. an outriggercomprising a structural frame arranged to be elevated by a hoist to aposition in front of a selected shelf on said rack, the outrigger havinghook means thereon arranged to engage the notched upright at each end ofthe selected shelf for releasably supporting the outrigger on saiduprights, e. the outrigger having rails thereon that align verticallyand horizontally with the rails on the selected shelf when the outriggeris so supported on the uprights to provide in effect an extension of therails on the shelf whereby the dolly may roll from the shelf onto theoutrigger, f. means on the dolly to restrain it from rolling off theshelf rails when the outrigger is not in front of the shelf and whichmay be released when the outrigger is supported at the front of theshelf, and g. means on the outrigger for limiting the travel of thedolly when it travels forward onto the rails of the outrigger.
 2. A racktype storage apparatus as defined in claim 1 in which said last namedmeans is so positioned that the rear wheels of the dolly cannot leavethe rails on the shelf.
 3. A rack type storage apparatus as defined inclaim 1 wherein the means to restrain the outrigger from rolling on theshelf rails when the outrigger is not positioned on the rack in front ofthe selected shelf comprises a latch on the dolly that interlocks withthe shelf structure and wherein there is means on the outriggerselectively operable to release said latch means only when the outriggerhas been secured to the uprights at the front of the selected shelf withthe rails of the outrigger aligned with the rails of the shelf.
 4. Arack type storage apparatus as defined in claim 3 wherein the latchcomprises a spring biased pin slidable within an enclosing barrel whichis secured to the dolly and having an end projecting from the barrel,the force oF the spring holding the pin projected into a latchingposition, the shelf having a structural section against a surface ofwhich the pin projects when the dolly is confined against travel alongthe shelf rails, said means on the outrigger for releasing said latchcomprising a cam on the outrigger positioned to selectively bear againstsaid pin to move it to a retracted position out of latching engagementwith said structural section of the shelf only when the outrigger hasbeen mounted on the rack with its rails aligned with the rails on therack, and means on the outrigger for operating the cam.
 5. A rack typestorage apparatus as defined in claim 4 wherein the outrigger has aninclined ramp thereon in the path of travel of said pin positioned toeffect retraction of the pin into the barrel when the dolly is movedfrom a position off the outrigger back onto the shelf.
 6. A rack typestorage apparatus as defined in claim 5 wherein each upright has aseries of parallel alternate notch and hook elements extending up eachside at the front thereof and the shelves have interfitting mountingmeans at each corner engaged with the notches and hooks of the uprights,and the hook means on the outrigger comprises vertically spaced cleatsat each end of the outrigger so located that notches in the frontuprights above and below the selected shelf are simultaneously engagedfor supporting the outrigger on the vertical columns at a level wherethe rails of the outrigger are aligned with the rails of the selectedshelf.
 7. A rack type storage apparatus as defined in claim 6 whereinthere are releasable safety means on the outrigger which are confined intheir operating position against the rear walls of the two verticalcolumns on which the outrigger is hung for preventing accidental releaseof the outrigger until said safety means are withdrawn from saidoperating position to release the outrigger for removal from theuprights.
 8. The invention defined in claim 7 wherein said safety meanshas a portion that projects beneath a hook of the column when the safetymeans is in operating position to restrain the outrigger againstaccidental upward movement of the column until the said safety means iswithdrawn from the operating position.